// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/win/iunknown_impl.h"

namespace base {
namespace win {

    IUnknownImpl::IUnknownImpl()
        : ref_count_(0)
    {
    }

    IUnknownImpl::~IUnknownImpl()
    {
    }

    ULONG STDMETHODCALLTYPE IUnknownImpl::AddRef()
    {
        base::AtomicRefCountInc(&ref_count_);
        return 1;
    }

    ULONG STDMETHODCALLTYPE IUnknownImpl::Release()
    {
        if (!base::AtomicRefCountDec(&ref_count_)) {
            delete this;
            return 0;
        }
        return 1;
    }

    STDMETHODIMP IUnknownImpl::QueryInterface(REFIID riid, void** ppv)
    {
        if (riid == IID_IUnknown) {
            *ppv = static_cast<IUnknown*>(this);
            AddRef();
            return S_OK;
        }

        *ppv = NULL;
        return E_NOINTERFACE;
    }

} // namespace win
} // namespace base
